Organic element for electroluminescent devices
View Patent ↗A phosphorescent electroluminescent device comprising a light-emitting layer containing a host material and a phosphorescent light-emitting material wherein the host material comprises a boron compound containing at least one boron-nitrogen bond. Such devices provide useful light emissions.
1. A phosphorescent electroluminescent device comprising a light-emitting layer containing a host material and a phosphorescent light-emitting material wherein the host material comprises a boron compound represented by formula (1):
wherein:
R 1 , R 2 , R 3a , and R 3b are independently selected substituents, provided that R 1 and R 2 may join with each other or with R 3a or R 3b to form a ring containing B.
2. An electroluminescent device as in claim 1 wherein the host material comprises a trisaminoborane material.
3. An electroluminescent device as in claim 2 wherein one of the amines of the trisaminoborane material is bonded to an aromatic ring group.
4. An electroluminescent device as in claim 2 wherein the three amines of the trisaminoborane material are each bonded to an independently selected aromatic ring group.
5. An electroluminescent device as in claim 2 wherein the trisaminoborane comprises an azolyl, azinyl, or arylamine group.
6. An electroluminescent device as in claim 2 wherein the trisaminoborane comprises an aminophenyl, carbazole, indole, or an aminonaphthyl group.
7. An electroluminescent device as in claim 2 wherein all three amino moieties are the same.
8. The device of claim 1 wherein at least one of R 3a and R 3b represents an aromatic ring group.
9. The device of claim 1 wherein R 1 and R 2 each represent an independently selected aromatic ring group.
10. The device of claim 1 wherein R 1 represents a 2,6-disubstituted benzene group.
11. The electroluminescent device of claim 1 wherein the host material is represented by formula 1 a,
wherein:
R 3a , R 3 , R 4a , R 4b , R 5c , and R 5b each represent an independently selected aliphatic group or aromatic group provided at least one of R 3a , R 3b , R 4a , R 4b , R 5a , and R 5b is an aromatic group and provided that two substituents may join to form a ring containing B.
12. The device of claim 11 wherein R 3a , R 3b , R 4a , R 4b , R 5a , and R 5d each represent independently selected aromatic groups.
13. The device of claim 1 wherein the host material is present in the light emitting layer at 25 wt % or greater.
14. The device of claim 1 wherein the host material is present in the light emitting layer at 50 wt % or greater.
15. The device of claim 1 wherein the host material is present in the light emitting layer at 80 wt % or greater.
16. The device of claim 1 wherein phosphorescent material emits blue light.
17. The device of claim 1 wherein the phosphorescent material emits green light.
18. The device of claim 1 wherein the phosphorescent material emits red light.
19. The device of claim 1 wherein the host material is selected from: structures Inv-1 through Inv-21:
20. The device of claim 1 wherein the light-emitting material is part of a polymer.
21. The device of claim 1 wherein the host material is represented by formula (1), wherein formula (1) is part of a polymer.
22. The device of claim 1 including a white light emitter.
23. The device of claim 1 including a fluorescent emitting material.
24. A display comprising the phosphorescent electroluminescent device of claim 1 .
25. An area lighting device comprising the phosphorescent electroluminescent device of claim 1 .
26. A process for emitting light comprising applying a potential across the device of claim 1 .